/* 重置和基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* 奢华配色系统 */
    --bg-primary: #0a0a0f;
    --bg-secondary: #1a1a2e;
    --bg-card: rgba(20, 20, 28, 0.8);
    --text-primary: #e8e8ea;
    --text-secondary: rgba(232, 232, 234, 0.7);
    --text-muted: rgba(232, 232, 234, 0.5);

    /* 金色渐变 */
    --gold-start: #d4af37;
    --gold-mid: #f4e5b8;
    --gold-end: #c5a028;

    /* 主题色 */
    --primary: #4a90e2;
    --primary-hover: #357abd;
    --secondary: #9b59b6;
    --accent: #e74c3c;

    /* 边框和阴影 */
    --border: rgba(120, 120, 140, 0.2);
    --shadow-sm: 0 2px 12px rgba(0, 0, 0, 0.15);
    --shadow-md: 0 8px 32px rgba(0, 0, 0, 0.25);
    --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.35);
    --shadow-gold: 0 0 40px rgba(212, 175, 55, 0.3);

    /* 渐变 */
    --gradient-gold: linear-gradient(135deg, var(--gold-start) 0%, var(--gold-mid) 50%, var(--gold-end) 100%);
    --gradient-primary: linear-gradient(135deg, #4facfe 0%, #00f2fe 50%, #43e97b 100%);
    --gradient-royal: linear-gradient(135deg, #1e3c72 0%, #2a5298 50%, #7e22ce 100%);
}

html {
    scroll-behavior: smooth;
    width: 100%;
    height: 100%;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: linear-gradient(165deg, var(--bg-primary) 0%, var(--bg-secondary) 50%, var(--bg-primary) 100%);
    background-attachment: fixed;
    background-size: 100% 100%;
    background-repeat: no-repeat;
    color: var(--text-primary);
    line-height: 1.7;
    min-height: 100vh;
    width: 100%;
    margin: 0;
    padding: 0;
}

/* 背景装饰 */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background:
        radial-gradient(circle at 20% 50%, rgba(74, 144, 226, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(155, 89, 182, 0.1) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(10, 10, 15, 0.9);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border);
    z-index: 1000;
    transition: all 0.3s ease;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo h1 {
    font-size: 1.5rem;
    font-weight: 800;
    background: var(--gradient-gold);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    filter: drop-shadow(0 0 20px rgba(251, 191, 36, 0.4));
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link:hover {
    color: var(--text-primary);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-gold);
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    margin: 3px 0;
    transition: 0.3s;
}

/* Hero 区域 */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 80px;
    position: relative;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-content {
    z-index: 2;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border);
    border-radius: 50px;
    font-size: 0.875rem;
    margin-bottom: 2rem;
}

.status-dot {
    width: 8px;
    height: 8px;
    background: #10b981;
    border-radius: 50%;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.hero-title {
    font-size: clamp(3rem, 8vw, 6rem);
    font-weight: 900;
    line-height: 0.9;
    margin-bottom: 1rem;
}

.title-aurora {
    display: block;
    background: linear-gradient(135deg, #fbbf24, #f59e0b, #d97706);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    filter: drop-shadow(0 0 40px rgba(251, 191, 36, 0.6));
}

.title-gold {
    display: block;
    background: linear-gradient(135deg, #60a5fa, #a78bfa, #f472b6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    filter: drop-shadow(0 0 40px rgba(168, 85, 247, 0.6));
}

.hero-subtitle {
    font-size: 1.25rem;
    font-weight: 300;
    letter-spacing: 0.3em;
    text-transform: uppercase;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.hero-description {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    max-width: 500px;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.btn {
    padding: 0.875rem 2rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    cursor: pointer;
    display: inline-block;
}

.btn-primary {
    background: white;
    color: black;
    position: relative;
    overflow: hidden;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 0 60px rgba(255, 255, 255, 0.4);
}

.btn-secondary {
    border: 2px solid rgba(255, 255, 255, 0.3);
    color: var(--text-primary);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.5);
}

.btn-outline {
    border: 2px solid var(--primary);
    color: var(--primary);
    background: transparent;
}

.btn-outline:hover {
    background: var(--primary);
    color: white;
}

/* Hero 视觉区域 - 星空宇宙效果 */
.hero-visual {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.space-container {
    position: relative;
    width: 100%;
    height: 500px;
    background: transparent;
    overflow: hidden;
}

/* 星空背景 */
.stars-field {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image:
        radial-gradient(2px 2px at 20px 30px, #eee, transparent),
        radial-gradient(2px 2px at 40px 70px, rgba(255,255,255,0.8), transparent),
        radial-gradient(1px 1px at 90px 40px, #fff, transparent),
        radial-gradient(1px 1px at 130px 80px, rgba(255,255,255,0.6), transparent),
        radial-gradient(2px 2px at 160px 30px, #ddd, transparent);
    background-repeat: repeat;
    background-size: 200px 100px;
    animation: twinkle 4s ease-in-out infinite alternate;
}

@keyframes twinkle {
    0% { opacity: 0.8; }
    100% { opacity: 1; }
}

/* 浮动光球 */
.floating-orbs {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(1px);
    animation: float-orb 8s ease-in-out infinite;
}

.orb-1 {
    width: 60px;
    height: 60px;
    background: radial-gradient(circle, rgba(74, 144, 226, 0.8) 0%, rgba(74, 144, 226, 0.2) 70%, transparent 100%);
    top: 15%;
    left: 20%;
    animation-delay: 0s;
    box-shadow: 0 0 30px rgba(74, 144, 226, 0.6);
}

.orb-2 {
    width: 40px;
    height: 40px;
    background: radial-gradient(circle, rgba(155, 89, 182, 0.8) 0%, rgba(155, 89, 182, 0.2) 70%, transparent 100%);
    top: 25%;
    right: 15%;
    animation-delay: 1.5s;
    box-shadow: 0 0 25px rgba(155, 89, 182, 0.6);
}

.orb-3 {
    width: 80px;
    height: 80px;
    background: radial-gradient(circle, rgba(212, 175, 55, 0.6) 0%, rgba(212, 175, 55, 0.1) 70%, transparent 100%);
    bottom: 30%;
    left: 15%;
    animation-delay: 3s;
    box-shadow: 0 0 40px rgba(212, 175, 55, 0.4);
}

.orb-4 {
    width: 35px;
    height: 35px;
    background: radial-gradient(circle, rgba(67, 233, 123, 0.8) 0%, rgba(67, 233, 123, 0.2) 70%, transparent 100%);
    bottom: 20%;
    right: 25%;
    animation-delay: 4.5s;
    box-shadow: 0 0 20px rgba(67, 233, 123, 0.6);
}

.orb-5 {
    width: 50px;
    height: 50px;
    background: radial-gradient(circle, rgba(244, 114, 182, 0.7) 0%, rgba(244, 114, 182, 0.2) 70%, transparent 100%);
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation-delay: 6s;
    box-shadow: 0 0 35px rgba(244, 114, 182, 0.5);
}

@keyframes float-orb {
    0%, 100% {
        transform: translateY(0px) translateX(0px) scale(1);
        opacity: 0.8;
    }
    25% {
        transform: translateY(-30px) translateX(15px) scale(1.1);
        opacity: 1;
    }
    50% {
        transform: translateY(-15px) translateX(-10px) scale(0.9);
        opacity: 0.9;
    }
    75% {
        transform: translateY(-25px) translateX(20px) scale(1.05);
        opacity: 1;
    }
}

/* 极光效果 */
.aurora-lights {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
}

.aurora {
    position: absolute;
    width: 100%;
    height: 2px;
    background: linear-gradient(90deg, transparent, rgba(74, 144, 226, 0.6), rgba(155, 89, 182, 0.6), rgba(67, 233, 123, 0.6), transparent);
    filter: blur(2px);
    animation: aurora-flow 6s ease-in-out infinite;
}

.aurora-1 {
    top: 20%;
    animation-delay: 0s;
    transform: rotate(-15deg);
}

.aurora-2 {
    top: 60%;
    animation-delay: 2s;
    transform: rotate(10deg);
    background: linear-gradient(90deg, transparent, rgba(212, 175, 55, 0.5), rgba(244, 114, 182, 0.5), transparent);
}

.aurora-3 {
    top: 80%;
    animation-delay: 4s;
    transform: rotate(-5deg);
    background: linear-gradient(90deg, transparent, rgba(155, 89, 182, 0.4), rgba(74, 144, 226, 0.4), transparent);
}

@keyframes aurora-flow {
    0%, 100% {
        opacity: 0.3;
        transform: translateX(-100px) scaleX(0.8);
    }
    50% {
        opacity: 0.8;
        transform: translateX(100px) scaleX(1.2);
    }
}

/* 脉冲效果 */
.space-container::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 200px;
    height: 200px;
    background: radial-gradient(circle, rgba(74, 144, 226, 0.1) 0%, transparent 70%);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    animation: pulse-space 4s ease-in-out infinite;
}

@keyframes pulse-space {
    0%, 100% {
        transform: translate(-50%, -50%) scale(1);
        opacity: 0.5;
    }
    50% {
        transform: translate(-50%, -50%) scale(1.5);
        opacity: 0.2;
    }
}

/* 滚动指示器 */
.scroll-indicator {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    animation: bounce 2s infinite;
}

.scroll-mouse {
    width: 24px;
    height: 40px;
    border: 2px solid var(--text-muted);
    border-radius: 12px;
    display: flex;
    justify-content: center;
    align-items: flex-start;
    padding: 8px 0;
}

.scroll-wheel {
    width: 4px;
    height: 12px;
    background: var(--text-muted);
    border-radius: 2px;
    animation: scroll-wheel 2s infinite;
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% { transform: translateX(-50%) translateY(0); }
    40% { transform: translateX(-50%) translateY(-10px); }
    60% { transform: translateX(-50%) translateY(-5px); }
}

@keyframes scroll-wheel {
    0% { opacity: 1; transform: translateY(0); }
    100% { opacity: 0; transform: translateY(12px); }
}

/* 分类区域 */
.categories {
    padding: 6rem 0;
    background: rgba(26, 26, 46, 0.3);
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-header h2 {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 900;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, var(--text-primary), var(--text-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-line {
    width: 100px;
    height: 4px;
    background: var(--gradient-primary);
    margin: 0 auto;
    border-radius: 2px;
}

.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.category-card {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border);
    border-radius: 20px;
    padding: 2rem;
    text-align: center;
    transition: all 0.3s ease;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.category-card::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: conic-gradient(from 0deg, transparent, var(--primary), transparent);
    opacity: 0;
    transition: opacity 0.3s ease;
    animation: rotate 4s linear infinite;
}

.category-card:hover::before {
    opacity: 0.1;
}

.category-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
}

.category-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.category-card h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.category-card p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.category-stats {
    color: var(--primary);
    font-weight: 600;
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

/* 文章区域 */
.articles {
    padding: 6rem 0;
}

.search-container {
    margin-bottom: 3rem;
    display: flex;
    justify-content: center;
}

.search-box {
    position: relative;
    max-width: 500px;
    width: 100%;
}

.search-box i {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
}

.search-box input {
    width: 100%;
    padding: 1rem 1rem 1rem 3rem;
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border);
    border-radius: 50px;
    color: var(--text-primary);
    font-size: 1rem;
    outline: none;
    transition: all 0.3s ease;
}

.search-box input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(74, 144, 226, 0.1);
}

.search-box input::placeholder {
    color: var(--text-muted);
}

.clear-btn {
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.clear-btn.show {
    opacity: 1;
}

.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.article-card {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border);
    border-radius: 20px;
    overflow: hidden;
    transition: all 0.3s ease;
    cursor: pointer;
}

.article-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
}

.article-image {
    width: 100%;
    height: 200px;
    background: var(--gradient-royal);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
    color: white;
}

.article-content {
    padding: 1.5rem;
}

.article-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    font-size: 0.875rem;
    color: var(--text-muted);
}

.article-category {
    background: var(--primary);
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
}

.article-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
    line-height: 1.4;
}

.article-card p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.6;
}

.article-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tag {
    background: rgba(74, 144, 226, 0.1);
    color: var(--primary);
    padding: 0.25rem 0.75rem;
    border-radius: 15px;
    font-size: 0.75rem;
    border: 1px solid rgba(74, 144, 226, 0.2);
}

.load-more {
    text-align: center;
}

/* 关于区域 */
.about {
    padding: 6rem 0;
    background: rgba(26, 26, 46, 0.3);
}

.about-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-text h2 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 2rem;
    background: var(--gradient-gold);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.about-text p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

.about-features {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-top: 2rem;
}

.feature {
    display: flex;
    align-items: center;
    gap: 1rem;
    color: var(--text-secondary);
}

.feature i {
    color: var(--primary);
    font-size: 1.25rem;
    width: 24px;
}

.about-stats {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.stat {
    text-align: center;
    padding: 2rem;
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border);
    border-radius: 20px;
}

.stat-number {
    font-size: 3rem;
    font-weight: 900;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.5rem;
}

.stat-label {
    color: var(--text-secondary);
    font-weight: 600;
}

/* 页脚 */
.footer {
    background: var(--bg-primary);
    border-top: 1px solid var(--border);
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.footer-section h3 {
    background: var(--gradient-gold);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.footer-section p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section ul li a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: var(--primary);
}

.social-links {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background: var(--primary);
    color: white;
    transform: translateY(-2px);
}

.footer-bottom {
    border-top: 1px solid var(--border);
    padding-top: 2rem;
    text-align: center;
}

.disclaimer {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: 1rem;
    padding: 1rem;
    background: rgba(231, 76, 60, 0.1);
    border: 1px solid rgba(231, 76, 60, 0.2);
    border-radius: 10px;
}

.footer-bottom p:last-child {
    color: var(--text-muted);
    font-size: 0.875rem;
}

/* 浮动联系按钮 - 优化版 */
.floating-contact {
    position: fixed;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    z-index: 1000;
}

.contact-btn {
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, #1e40af 0%, #3b82f6 50%, #60a5fa 100%);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: 25px 0 0 25px;
    text-decoration: none;
    box-shadow:
        0 8px 32px rgba(59, 130, 246, 0.3),
        0 4px 16px rgba(0, 0, 0, 0.2);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    position: relative;
    overflow: hidden;
}

.contact-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s ease;
}

.contact-btn:hover::before {
    left: 100%;
}

.contact-btn:hover {
    background: linear-gradient(135deg, #1d4ed8 0%, #2563eb 50%, #3b82f6 100%);
    box-shadow:
        0 12px 48px rgba(59, 130, 246, 0.4),
        0 6px 24px rgba(0, 0, 0, 0.3);
    transform: translateX(-5px);
}

.contact-btn i {
    font-size: 1.5rem;
    margin-right: 0.75rem;
    animation: pulse-icon 2s ease-in-out infinite;
}

@keyframes pulse-icon {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

.contact-btn span {
    display: flex;
    flex-direction: column;
    line-height: 1.2;
}

.contact-btn span div:first-child {
    font-weight: 700;
    font-size: 0.95rem;
    margin-bottom: 2px;
}

.contact-btn span div:last-child {
    font-size: 0.8rem;
    opacity: 0.9;
    font-weight: 400;
}

/* 返回顶部 */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 50px;
    height: 50px;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 1000;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--primary-hover);
    transform: translateY(-2px);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background: rgba(10, 10, 15, 0.95);
        backdrop-filter: blur(20px);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: var(--shadow-md);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .hamburger {
        display: flex;
    }

    .hamburger.active span:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active span:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .hamburger.active span:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }

    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2rem;
    }

    .hero-visual {
        order: -1;
    }

    .space-container {
        height: 300px;
    }

    .orb-1, .orb-2, .orb-3, .orb-4, .orb-5 {
        transform: scale(0.8);
    }

    .aurora {
        height: 1px;
    }

    .hero-buttons {
        justify-content: center;
    }

    .categories-grid {
        grid-template-columns: 1fr;
    }

    .articles-grid {
        grid-template-columns: 1fr;
    }

    .about-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .about-stats {
        flex-direction: row;
        justify-content: center;
    }

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .floating-contact {
        position: fixed;
        right: 0;
        top: 50%;
        transform: translateY(-50%);
        z-index: 1001;
    }

    .contact-btn {
        border-radius: 25px 0 0 25px;
        padding: 0.875rem 1rem;
        box-shadow:
            0 8px 32px rgba(59, 130, 246, 0.4),
            0 4px 16px rgba(0, 0, 0, 0.3);
    }

    .contact-btn span {
        display: none;
    }

    .contact-btn i {
        margin-right: 0;
        font-size: 1.75rem;
    }

    /* 返回顶部按钮移到左下角避免重叠 */
    .back-to-top {
        bottom: 2rem;
        left: 2rem;
        right: auto;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 1rem;
    }

    .nav-container {
        padding: 1rem;
    }

    .hero {
        padding-top: 100px;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .section-header h2 {
        font-size: 2rem;
    }

    .category-card,
    .article-card {
        margin: 0 1rem;
    }

    /* 确保小屏幕上的按钮布局 */
    .floating-contact {
        right: 0;
        top: 50%;
        transform: translateY(-50%);
    }

    .contact-btn {
        padding: 0.75rem 0.875rem;
        border-radius: 20px 0 0 20px;
    }

    .contact-btn i {
        font-size: 1.5rem;
    }

    .back-to-top {
        bottom: 1.5rem;
        left: 1.5rem;
        width: 45px;
        height: 45px;
    }
}